1. Field of the Invention
The present invention relates to a method of probing circuit devices such as the integrated circuits formed on a semiconductor wafer.
2. Description of the Related Art
Probing is one of those methods which are intended to measure the electric characteristic of each of devices such as ICs in the course of manufacturing these devices. This probing is carried out in such a way that each of matters to be measured, that is, each of semiconductor devices or chips pattern-formed on a semiconductor wafer is electrically connected to the tester which comprises measuring instruments and the like by probes of the probe device to measure the electric characteristic of the semiconductor chip.
Before this measurement is carried out, however, positioning is needed to accurately contact the probes with electrode pads of each of the semiconductor chips on the wafer. As a step previous to this measurement, therefore, the operator carries out the positioning operation relative to a first wafer, which is called a teaching process. Data obtained by the positioning operation are stored and then used to automatically carry out the positioning of wafers which will follow before the measurement is applied to each of the wafers.
Conventionally, the operator starts measuring each of the following wafers just after the data are obtained while positioning the first wafer.
When each of the following wafers is measured using the data obtained in the course of operator's positioning the first wafer, however, it sometimes happens that the measuring probes are not accurately positioned relative to the electrode pads of each of the semiconductor chips formed on the wafer. The conventional positioning manner, however, has no measure for confirming how the probes are positioned relative to the electrode pads of each of the semiconductor chips on the wafer. This therefore forces the operator to again repeat the positioning operation relative to the second wafer, namely the teaching process by his hands.